The Boswyns development accommodates a 15 bed residential detoxification facility funded by a grant awarded by the Department of Health. The development provides a facility for drug users in need of a residential environment. The service offers medical, nursing, social and education interventions, within a supportive and non-institutional milieu and also offers a range of non-medical interventions such as life skills training, educational programmes and leisure pursuits. The concept of the scheme came from the ancient Cornish settlements of Carn Euny and Chysauster. These settlements were very organic in form; they effectively grew out of the ground using locally sourced stone. From the original conceptual design, the development of the new facility has been driven by a wish to reduce the impact of the building on the surrounding environment and reduce the operating costs through energy efficiency and simplicity. The overall building aesthetics respects the relief of the site to ‘blend in’ when viewed from distance and construction materials have been selected to minimise resources from non-sustainable sources; timber frame, larch cladding, green roofs, locally reclaimed stone walling. In addition to these measures the levels of insulation being targeted are 20% better than current Building Regulation requirements and robust construction is being specified to reduce infiltration and air leakage.